The present embodiments relate to a local coil.
Imaging systems that are based on a method of magnetic resonance measurement (e.g., of nuclear spin; magnetic resonance tomography) may be used for a wide range of applications. With this type of image acquisition, a powerful static basic magnetic field B0 is used for the initial alignment and homogenization of magnetic dipoles that are to be examined. For the determination of material properties of an object of examination that is to be imaged, the dephasing or relaxation time is determined after a deflection of the magnetization out of the initial alignment, such that various different material-typical relaxation mechanisms or relaxation times may be identified. The deflection may be attained via a number of HF pulses using an HF transmitter device of the magnetic resonance imaging system. A suitable measurement of the magnetization at the particular moment of the object under examination for the determination of the material-typical relaxation times and material-typical properties is effected with the aid of receiver coils that are matched to the material-typical properties. In order to improve the quality of the magnetic resonance recording, it is advantageous for these receiver coils to be arranged in the immediate vicinity of the object under examination or of a patient or test subject. Such receiver coils or transmitter coils, which are arranged in the immediate vicinity of the object under examination, are known by the term “local coils”.
In order to obtain the advantages of being located close to the object such as, for example, a favorable signal-to-noise ratio, the relative position of the local coil in relation to the object under examination during a recording sequence is to be determined in a defined manner.
By way of example, various fixing mechanisms are known, such as tension bands and the like, which make possible the fixation of the local coils in relation to the patient (e.g., the test subject). For example, a local coil may be fixed on or around a wrist, a knee, or the like. Because the local coil may only be adapted to a certain degree to the object under examination, additional wedge elements or foam inlays may be used in order to retain the local coil in a specifically determined position in relation to the object under examination. This vastly delays the sequence of operational steps for the acquisition of magnetic resonance images, as well as being unpleasant for the test subject.